Glass tabletop



FIG. 1 is a perspective view of a glass tabletop showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front elevational view thereof, the rear elevational view being a mirror image of FIG. 3;

FIG. 4 is a right end view thereof, the left end view being a mirror image of FIG. 4; and

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a glass tabletop, as shown and described. 